Project Summary/Abstract Dr. Joseph?s long-term goal is to become an independent physician-investigator specializing in identification of neonatal and infant precursors to the development of Attention-Deficit/Hyperactivity Disorder (ADHD) and early interventions aimed at preventing symptom expression in children at risk for ADHD. She has expertise in assessment and treatment of ADHD from childhood to adulthood. This K23 career development award will allow her to emerge as one of the few physician-investigators prepared to evaluate neonates and infants at risk for developmental disorders. In recent work Dr. Joseph evaluated child behaviors among preschool-aged children born to fathers with and without childhood ADHD. She found that children at familial risk for ADHD were observed to have dysregulated behavior as early as 3 years of age, a potential indicator of the eventual development of ADHD. To study earlier precursors of ADHD, Dr. Joseph aims to receive training in (1) the longitudinal course of childhood ADHD including the variability in ADHD symptoms over time and range of functional outcomes (2) the cognitive development of attention from birth through childhood to understand how inattention in infancy may serve as an early indicator of atypical development; and (3) advanced statistical methods in the analysis of longitudinal data. These aims will be accomplished through a combination of coursework, directed readings, and tutorials. Dr. Joseph?s mentorship team is comprised of Drs. Brooke Molina (primary mentor), a leader in the field of ADHD specializing in course and outcomes for individuals with the disorder, Jana Iverson (co-mentor), an expert in atypical development and identification of infants at-risk for neurodevelopmental disorders, and Erik Thiessen (secondary mentor), a specialist in the cognitive development in infancy, along with knowledgeable consultants with complementary skill sets. The University of Pittsburgh offers a strong research environment in which to train with supports for professional development and infrastructure to aid in participant recruitment. Offspring (N=100), half with a parent with ADHD, will be assessed serially as neonates (brith-1 month) and infants (8-10 months) with parent reported behavior collected in toddlerhood (18 months) to compare indices of attention in offspring at high vs. low risk for ADHD (Aim 1) and evaluate neonate and infant indices of attention as predictors of toddler attention (Aim 2). Parent?s joint attention with their infant will be examined in relation to parent ADHD status and offspring attention in toddlerhood (Aim 3). Data from this project may provide initial evidence for the utility of novel early markers of childhood inattention detectable in the first year of life, a critical step towards early identification and intervention for childhood ADHD. The proposed study aligns with NIMH strategic objective 2 to chart mental illness trajectories including characterization of developmental dimensions in behavior to determine optimal timing of intervention.